Pipette



June 15 1926.

1,589,056 L. E. DRUMMOND y PIPETTE Filed July 1I 1925 INVENToR.

L 5.24m BY. Mlm/- Gif@ 4* ATTORNEY.

Patented June 15, 1926.

`UbllflLED STATES 1,589,05@ PATENT QFFIQE.

'LOUIS E. DRUMMOND, GF NILLISTOWN TOWNSHIP, CHESTER COUNTY, PENN- SYLVANIA.. i

PIPETTE.

'Application flied truly i,

My invention relates to an attachment for a pipette or other similar article or apparatus. Y

In accordance with my invention an at-` tachment, herein termed a cup-stopper, formed of metal or other suitable material is carried by the rubber tube forming part of the pipette and is adapted to be hooked over the end of the pipette stem.

Further, in accordance with my invention the cup-stopper is constructed in any desired manner so as to permit adjustment relative to, or ready withdrawal from., the rubber tube. i

Further, in accordance with my invention tension is exerted by the rubber tube when the cup-stopper is positioned on the end ot the pipette stem.

Further, in accordance with my invention the cup-stopper is provided with a wad of soft or flexible material.

My invention resides in apparatus of the character hereinafter described and claimed.

For an illustration of one ot the forms my invention may take, reference is to be had to the accompanying drawing, in which:

Figure l is a plan view oi a pipette with the cup-stopper in position on the rubber tubing. p

Fig. 2 is aview, partly in section, showing the cup-stopper in engagement with the end ol' the pipette stem.

Fig. 3 is a perspective view of the cupstopper.

Referring to l and 2 ot' the drawing, a. represents the pipette stem formed of glass and having the longitudinally restricted passage Z). The passage Z) opens into an enlarged, bulb-like opening` c formed in any suitable manner. Connnunieating` with the bulb c on its opposite side is another restricted passage (l, opening in turn into the enlarged space e formed at one end ot the pipette. stem to. lVithin the bulb o is the pellet having a dian'ieter suliiciently large to prevent entry into the passages b or al.

Attached to one end of the pipette stein is the rubber tube g provided at its far end with the glass mouthpiece it.

The device described above is widely used by membersof the medical profession. In oaeratio-n, the pointed end of the stern is placed in engagement with a drop oipblood obtained by puncturing the slrin et the pa= titan lflie physician their ii ,15:11am

1925. Serial No. 40,723.

ber 7L in his mouth and by suction causes the proper amount ot' blood to ente-r passage 'flhereatten a suitable amount ot dilutingl solution is likewise introduced through the passage Finally, by shaking the stem,

the pellet f causes thorough mixing ol' the blood and diluting solution in the bulb c.

At this stage, the pipette with the speci'- men oi? blood contained therein must be transported to a laboratory having proper apparatus for counting the blood corpuseles.

vIt becomes necessary, therefore, to tempo-- .the result beingthat another trip to the patient is necessitated.

My invention overcomes the dir'liculties that have heretofore been experienced in using devices of this character. As shown onthe drawing, I provide a cup-stopper adapted for clutching or` other suitable engagement with the rubber tube. This cupstopper is formed of metal or other suitable material and comprises a cup portion e' having a depending shank y'. The shank is perforated as shown at le and is provided 'with a laterally extending ring-like member Z. Preferably, the member Z is formed. integral with the shank y', but it is to be understood that it may be termed separately and attached to the shank in any suitable manner. Further, it is to be understood that the member Z may be broken away onthat side removed from the shank, `thereby forming, in eliect, two curved prongs, each eX- tending `partly around the rubber tube. Inserted in the cup portion il and held therein is a rubber cushion m or other suitable soft, flexible material such as cork. This cushion is adapted to tightly close the open end ot the stem when the cup-stopper is in position thereon.

As shown in Figs. 1 and 2, therubber tube g has been inserted through the perforation 7c and the ring-like member Z. Due

to the 'fact that the plane of the ring-like member Z is disposed at an angle of substantially 90o' to that of the shank j,the portion 'if the rubber tube rdjaent land passing ,ti the porter' n fr-reed sume and retain an angular position with respect to shank j, the result being that the cup-stopper is normally held in fixed position on the rubber tube. As shown in Fig. 1, the cup-stopper is positioned on the rubber tube a variable distance from the top of the pipette stem somewhat less than the length of the stem. After the specimen has been obtained, the rubber tube g is bent as is shown in Fig. 2, and then stretched so as to permit the cup portion e' to be hooked over the pointed end of' the stem. This simple operation places the device in condition for transportation to the laboratory.

It will be observed that once the cupistopper is placed as shown in Fig. 2, the tension of the rubber tube will positively retain it in that position. lt Will also be observed that by my arrangement the pipette stem is closed at one end by the kink in the rubber tube and at the other end by the material in the cup-stopper and that both ends are closed sin'mltaneously and by a simple operation. Further, it ivill be observed that with the cup-stopper in position on the end of the stem, there is an absence of lateral strain on this member.

lvlhat I claim is:

l. The combination with a pipette having a stem and a flexible tube attached thereto, of a member including a cup-stopper carried by said flexible tube at a. distance from said stem subttantially less than the length of the ste-1n.

2. The combination With a pipette having a stem and a flexible tube attached thereto, of a member including` a cup-stopper detachably carried by said flexible tube at a distance from said stem substantially less than the length of the stein.

3. The combination With a pipette having a stem and a flexible tube attached thereto, of a member including a cup-stopper adjust-ably carried by said flexible tube at a distance from said stem substantially less than the length of the stem.

Ll. The combination with a pipette having a stem and a` flexible tube attached thereto, of a member including a cup-stopper carried by said flexible tube, and soft flexible material in said cup-stopper.

The combination With a pipette having a stem and a exible tube attached thereto, of a member including a cup-stopper secured to said flexible tube, and a rubber cushion in said cup-stopper.

6. The combination with a pipette having a stem and a flexible tube attached thereto, of a member carried by said tube and including a cup-stopper adapted to be hooked over the free end of the stem.

7 The combination with a pipette having a stem and a flexible tube attached thereto. of a cup-stopper carried by said tube, said cup-stopper comprising a perforated shank, a laterally extending ring and a member forming an open chamber.

S. The combination With a pipette having a stem and a flexible tube attached to one end of the stem, of' a member including a cup-stopper adapted to be hooked over the free end of the stem, said member being carried by the flexible tube at such position that appreciable tension must be exerted thereon to permit connection of the stem and cup-stopper.

9. A sealed pipette comprising a stem, provided with a longitudinal passage, a flexible tube connected to said stem at one end and reversely bent, and a cup-stopper attached to said flexible tube and closing the other end Of said stem.

10. rThe combination with a. pipette having a stein and a flexible tube attached thereto, of a cup-stopper carried by said tube and placed over the open end of said stem, the flexible tube exerting tension en the 'cupstopper' and holdingthe same in place.

11. The combination with a pipette having a stem and a fiexible tube attached thereto, of a cup stopper carried by said tube and hooked over the open end of said stem, the `flexible tube being under tension and holding the cup-stopper in place, and a rubber cushion in the cup-stopper.

An attachment carried by the flexible tube of a pipette comprising a cup-like element adapted to close the open end of the pipette.

13. An attachment carried by the flexible tube of a pipette comprising a shank having a cup-like element adapted to close the open end of the pipette.

1l. An attachment carried by the flexible tube of a pipette comprising a shank having a laterally extending part and a cup-like element adapted to close the open end of the pipette.

15. An attachment carried by the flexible tube of a pipette comprising a perforated shank having a laterally extendingpart and a cup-like element adapted to close the open end of' the pipette.

1G. An attachment carried by the flexible tube of a pipette comprising a perforated shank provided With a cup-like element adapted to close the open end of the i'iipette.

li". An attachment carried by the flexible tube of a pipette comprising a shank having a cup-like element and soft flexible material in said cup-like element adapted to close the open end of the pipette. l

18. A n attachment carried by the flexible tube of a pipette comprising a shank having a cup-like element and a rubber cushion in said cup-like element adapted to close the open end of the pipette.

LOUIS E. DRUMMOND. 

